Unplugged mine 10 hrs ago and at 67% battery. Seidio slim extended battery ftw! Could be better but I refuse to moderate my usage or play around with my settings. Btw I'd usually be at about 40% battery with the stock battery.
Just read up on what those settings do.. no real danger or you wouldn't have access.
Your simply turning on or off certain functions/abilities.
All the nasty stuff is hidden behind access codes the normal user doesn't know how to get to and is not available in the simple menu of the phone.
I agree changing some settings will improve battery life. I just prefer to leave stuff like wifi, mobile data, background sync, and auto brightness active. I also limit the apps running in the background to only the essential ones for me.
Other than that I like using the phone when I want and how I want without having to be concerned about battery life. Unfortunately the real world doesn't always cater to my wants. Having the extended battery helps though.